Safety device for presses



May 7, 1940.

B. J. VICTOR SAFETY DEVICE FOR PRESSES 3 Sheets-Sheet! 1 Filed Aug. 7,1937 ATTOF/VZY May 7, 1940. B. J. VICTOR SAFETY DEVICE FOR PRESSES aSheets-Shet 2 Filed Aug. 7, 1937 May '7, 1940; a J; VI TOR 2,199,766

SAFETY DEVICE FOR PRESSES Filed Aug. 7, 1937 s Sheets-Sheet 's BfN/AM/A/9/. V/6 70/? MMWWA I Patented May 7, 1940 PATENT OFFICE SAFETY DEVICEFOR PRESSES Benjamin J. Victor, Oak Park, Ill., assignor to VictorManufacturing & Gasket Company, Chicago, 111., a corporation of IllinoisApplication August '7,

'7 Claims.

This invention relates to an improved safety device, particularly forpunch presses and the like, and has, for one of its principal objects,the provision of means whereby the punching or downward motion of thepress .will be immediately and positively stopped in the event ofbreakage of oneof the parts, preventing undesirable movement resultingfrom inertia or momentum, which movement might possibly cause badaccidents.

The construction of the present device constitutes an improvement overthe apparatus shown and described in my prior Patent No. 1,865,806,entitled Safety attachment for punch presses, dated July 5, 1932.

-A further object of the invention is to provide a simple yet efiicientsafeguard for the operators of punch presses of various types wherebythe punching action will be instantly terminated in the event ofaccidental breakage of any part, particularly when the operators hand orfingers would, in the normal course of operation, be in the proximity ofthe dies.

Other and further important objects of the g5 invention will be apparentfrom the disclosures in the accompanying drawings and followingspecifications.

The invenion, in a preferred form, is shown in the drawings andhereinafter more fully described.

In the drawings:

Figure 1 is a front elevation of a punch press of the usual type,particularly that known as the back-geared press, and the figureincludes a 5 showing of portions of the safety device of this inventionas applied to the press.

Figure 2 is a detail view of parts of the apparatus shown in Figure 1.

Figure 3 is a side elevation of a press, showing the safety device ofthis invention applied thereto.

Figure 4 is a rear view of the press, illustrating further portions ofthe safety apparatus.

As shown in the drawings:

The reference numeral [0 indicates generally the frame of a punch pressof the gear type, having the usual driving gears l2 operated from ashaft [4 and driving pulleys l6 upon which a belt I8 is mounted.

The movable portion of the press is illustrated at 29, and one safetyfeature embodies a pair of depressible handles 22, one at each side ofthe device, each handle being connected by a chain or the like 24 to ahinged element 25, which elements are withdrawn into the position shown1937, Serial No. 157,877

in dotted lines by a downward movement of the handles 22 whenever it isdesired to operate the mechanism. I

Curved rods 28 surrounded by coil springs 3|) are fastened to the blocks26 in such a manner that the blocks are normally propelled into thefull-line position.

Obviously, if the blocks are in the position shown in full lines, thehead 20 of the punch will not be allowed to descend into punching orworking position against whatever material is on the bed 32 of thedevice.

In this event, downward movement of the head will also force the element34 downwardly, as this will be impelled because the blocks 26 are intheir full-line positions. This element 34 will be allowed to movedownwardly until such time as the pins or bolts 36 in the slots 38 inthe element 3 lwil1 contact the upper ends of the slots.

Before this: happens, however, provision is made for an automaticstoppage of the machine by reason of a projection or lug 4B which iswelded or otherwise fastened on the element 34 and which, in thedownward movement of the element 34, will contact one end of abell-crank lever 42 (Figure 3) which is pivoted at 44 on the machine andto the inner end of which is attached a link 46.

The lower end of the link is pivotally attached at 48 to a latch element56 which is pivotally mounted at 52 on the machine, and this latchelement normally retains the lower end of a brake release rod 54 ininoperative position.

A heavy coiled spring 56 (Figure 4) is mounted on a shaft 58 which runstransversely of the press and is normally held in compressed position byreason of the action of the latch 50.

However, when due to some accident, the latch 50 is tripped by reason ofmotion of the bellcrank lever 62, the spring 56 immediately comes intooperation, pushing the brake rod 54 outwardly about its pivotal support68, and this, in turn, operates to set the inner shoe 62 of a brakeelement against the corresponding outer cone 64. As will be evident froman inspection of Figure 4, the shoe 62 is mounted on the driving shaft14 of the device, and as soon as this comes in contact with the innerface of the fixed brake cone element 64, the punch press action isimmediately stopped, this stoppage being also due to the fact thatclutch elements 66 are, at the same time, withdrawn from correspondingrecesses in the driving pulley l6.

It will, therefore, be obvious that installation of this safety deviceon any punch press will tend to eliminate casualties or other accidentsinasmuch as no free motion of the punch elements is allowed at any timeafter a breakage or any other improper operation of a part.

I am aware that many changes may be made and numerous details ofconstruction varied throughout a wide range without departing from theprinciples of this invention, and I, therefore, do not purpose limitingthe patent granted hereon otherwise than as necessitated by the priorart.

I claim as my invention:

1. A safety device for presses, including clutch and brake elements onthe driving shaft of the press, means for instantly releasing the clutchand setting the brake, said means including a spring-pressed rodextending transversely of the press, and latch means for normallyretaining the rod in retracted position, together with a bellcrank levermounted on the side of the press, a link connecting the bell-crank leverto the latch and means for automatically releasing the latch onaccidental undesired operation of the press.

2. A safety device for presses, including clutch and brake elements onthe driving shaft of the press, means for instantly releasing the clutchand setting the brake upon accidental undesired operation of any part ofthe press, said means including a spring-pressed rod, latch means fornormally retaining the rod in retracted position, a bell-crank levermounted on the side of the press, and a link connecting the bell-cranklever to the latch, and a projection on the movable portion of the pressadapted to contact the end of the bell-crank lever upon undesirabledownward movement.

3. A safety device for presses, including clutch and brake elements onthe driving shaft of the press, means for instantly releasing the clutchand setting the brake upon accidental undesired operation of any part ofthe press, said means including a spring-pressed rod, latch means fornormally retaining the rod in retracted position.

, a bell-crank lever mounted on the side of the press, a link connectingthe bell-crank lever to the latch, a projection on the movable portionof the press adapted to contact the end of the bell-crank lever uponundesirable downward movement, and a pair of safety blocks normallypositioned below the head of the press.

4. A safety device for presses, including clutch and brake elements onthe driving shaft of the press, means for instantly releasing the clutchand setting the brake upon accidental undesired operation of any part ofthe press, said means for temporarily removing the safety blocks frombeneath the press head for normal operation thereof.

5. A safety device for presses, including clutch and brake elements onthe driving shaft of the press, means for instantly releasing the clutchand setting the brake upon accidental undesired operation of any part ofthe press, said means including a spring-pressed rod, latch means fornormally retaining the rod in retracted position, a bell-crank levermounted on the side of the press, a link connecting the bell-crank leverto the latch, a projection on the movable portion of the press adaptedto contact the end of the bellcrank lever upon undesirable downwardmovement, a pair of safety blocks normally positioned below the head ofthe press, handles for temporarily removing the safety blocks frombeneath the press head for normal operation thereof, said handles beingpivotally mounted, one on each side of the press and chain connectionsbetween the handles and said blocks.

6. A safety device for presses, including a clutch and brake elements onthe driving shaft of the press, means for instantly releasing the clutchand setting the brake upon accidental undesired operation of any part ofthe press, said means including a spring-pressed rod, latch means fornormally retaining the rod in retracted position, a bell-crank levermounted on the side of the press, a link connecting the bellcrank leverto the latch, a projection on the movable portion of the press adaptedto contact the end of the bell-crank lever upon undesirable downwardmovement, a pair of safety blocks normally positioned below the head ofthe press, handles for temporarily removing the safety blocks frombeneath the press head for normal operation thereof, said handles beingpivotally mounted, one on each side of the press, chain connectionsbetween the handles and said blocks, and pins projecting from the presshead.

'7. A safety device for presses, including a clutch and brake elementson the driving shaft of the press, means for instantly releasing theclutch and setting the brake upon accidental undesired operation of anypart of the press, said means including a spring-pressed rod, latchmeans for normally retaining the rod in retracted position, a bell-cranklever mounted on the side of the press, a link connecting the bellcranklever to the latch, a projection on the movable portion of the pressadapted to contact the end of the bell-crank lever upon undesirabledownward movement, a pair of safety blocks normally positioned below thehead of the press, handles for temporarily removing the safety blocksfrom beneath the press head for normal operation thereof, said handlesbeing pivotally mounted, one on each side of the press, chainconnections between the handles and said blocks, and pins projectingfrom the press head, said pins mounted for longitudinal movement inslots in the press body.

BENJAMIN J. VICTOR.

